Issue #20344 has been reported by nobu (Nobuyoshi Nakada). ---------------------------------------- Bug #20344: argument stack underflow (-1) https://bugs.ruby-lang.org/issues/20344 * Author: nobu (Nobuyoshi Nakada) * Status: Open * Backport: 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED, 3.3: REQUIRED ---------------------------------------- This file produces argument stack underflow, since ruby 2.5. ```ruby proc do next if true case nil when "a" next when "b" when "c" proc {} end next unless true end ``` ``` -- raw disasm-------- trace: 100 0000 nop ( 1) <L000> [sp: 0, unremovable: 1, refcnt: 5] trace: 1 <L004> [sp: 0, unremovable: 0, refcnt: 1] adjust: [label: 0] 0001 putnil ( 2) 0002 leave ( 13) <L008> [sp: 1, unremovable: 0, refcnt: 1] adjust: [label: 0] 0003 putnil ( 6) 0004 leave ( 13) adjust: [label: 8] 0005 jump <L005> ( 5) 0007 pop ( 7) 0008 jump <L005> ( 7) * 0010 pop ( 8) trace: 1 <L011> [sp: -1, unremovable: 1, refcnt: 1] 0011 putself ( 9) 0012 send <calldata:proc, 0>, nil ( 9) <L012> [sp: -1, unremovable: 0, refcnt: 2] 0015 pop ( 9) <L005> [sp: 1, unremovable: 0, refcnt: 2] trace: 1 0016 putnil ( 12) <L001> [sp: -1, unremovable: 0, refcnt: 3] trace: 200 0017 leave ( 13) --------------------- ``` -- https://bugs.ruby-lang.org/